Room air conditioner fresh air intake duct

ABSTRACT

An elongated semi-cylindrical conduit damper rotatably supported about one end on the partition shround wall of a room air conditioner adjacent the evaporator centrifugal fan orifice with a fresh air opening in the wall aligned on one side of its axis of rotation. The conduit is biased to a first selected closed position in which a peripheral flange defining its elongated mouth is in continuous flush contact with the partition wall preventing passage of outside air through the wall opening. The conduit damper being rotatable to a second selected open position with its semi-spherical free end disposed in the path of the evaporator fan orifice so as to communicate a portion of its mouth therewith whereby the conduit provides an air flow passage connecting the suction side of the evaporator fan to the fresh air opening causing fresh air to be drawn through the conduit and the fan orifice for distribution to the room being conditioned.

United States Patent 1 I 1 3,727,424

Edens et al. 5] Apr. 17, 1973 ROOM AIR CONDITIONER FRESH AIR INTAKE DUCT Primary Examiner-William .l. Wye Attomey-Willia.m S. Pettigrew et al.

[75] Inventors: William G. Edens; John H. Loos,

both of Dayton; Emerson L. Wark, qBSTR q Vandalia, all of Ohio [57] CT An elongated semi-cylindrical conduit damper [73] Asslgnee: Mom's Corporation rotatably supported about one end on the partition Daron Mlch' shround wall of a room air conditioner adjacent the 22 Filed; Man 31 9 72 evaporator centrifugal fan orifice with a fresh air opening in the wall aligned on one side of its axis of [21] PP N05 239,954 rotation. The conduit is biased to a first selected closed position in which a peripheral flange defining 52 US. Cl. ..62/262, 98/94, 62/427 its is cqnfimmus flush the partition wall preventing passage of outside air [51] Int. Cl ..F25d 23/12 through the wall opening. The conduit damper being [58] Field of Search ..98/94, 94 AC,

62/262 427 rotatable to a second selected open position with its 7 semi-spherical free end disposed in the path of the 1 evaporator fan orifice so as to communicate a portion [56] References C'ted of its mouth therewith wherebythe conduit provides UNITED STATES P ATENTS an air flow passage connecting the suction side of the evaporator fan to the fresh arr opening causing fresh 2,540,957 2/1951 Newton ..62/262 X ahto be drawn through the conduit and the fan orifice 2,71 1,086 6/1955 Eilers for distribution to the room conditioned 2,711,087 6/1955 Jennings 2,971,351 2/1961 Webster ..62/427 8 Claim, 10 Drawing Figures Z 4" Z L r4 5i .i

PATENTEDAPR 1 71973 SHEET 1 [IF 3 ROOM AIR CONDITIONER FRESH AIR INTAKE DUCT This invention relates to room air conditioning units and more particularly to a fresh air conduit damper for providing outside air flow into the unit.

Most air conditioners provide manually selective damper control means in which fresh air is either drawn in or stale room air exhausted from the room. Prior art air conditioners have accomplished the introduction of a small amount of fresh air into the room by means of damper arrangements associated with an opening in the dividing wall between the condenser and evaporator compartments. The instant invention concerns a rotable elongated half-round conduit damper having a fresh air partition wall opening on one side of its axis of rotation designed so that when fresh air is desired the semispherical free end of the conduit cavity elongated mouth is rotated over a portion of the evaporator fan suction air inlet orifice. When the fan is operating the air entering the evaporator fan suction inlet is at a negative pressure causing a negative pressure within the conduit resulting in fresh air being pulled into the fan and distributed to the room being conditioned through suitable discharge passages. Upon the conduit damper being rotated to its biased normally closed position the conduits peripheral flange defining the elongated mouth is moved intoflush relationship with the adjacent planar shroud wall to thereby close the fresh air opening against the passage of outside air.

It is therefore an object of this invention to provide a room air conditioner wherein an elongated semi-cylindrical conduit is rotatably supported on the evaporator fan partition shroud wall about one semi-spherical end enclosing a fresh air inlet on one side of its axis of rotation such that when its free semi-cylindrical end is rotated over a portion of the suction orifice of the centrifugal fan by manual control means fresh air is drawn through the shroud wall inlet and into the suction orifice for discharge to the room being conditioned, the conduit cutting off communication between the fresh air inlet and the evaporator orifice when the conduit is rotated to its closed position flush with the adjacent planar wall of the shroud wall.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

FIG. 1 is a top plan view of a room air conditioner having an arrangement according to the invention;

FIG. 2 is a vertical sectional view taken substantially along the lines 2-2 of FIG. 1;

FIG. 3 is a sectional view taken on the line 3-3 of FIG. 2 showing the pivotal connection of the semicylindrical conduit structure;

FIG. 4 is an exploded view of the pivotal end of the conduit, securing collar and biasing spring;

FIG. 5 is a fragmentary vertical plan view taken on the line 5-5 of FIg. 1;

FIG. 6 is a vertical fragmentary plan view of the exhaust and intake baffles taken on the line 6-6 of FIG.

FIG. 7 is a vertical sectional view taken on the line 7-7 of the conduit of FIG. 4;

FIG. 8 is a fragmentary sectional view taken on the line 8-8 of FIG. 2;

FIG. 9 is a fragmentary view partly in section taken on the line 9-9 of FIG. 8;

FIG. 10 is a fragmentary sectional view taken on the line 10-10 of FIG. 9.

Referring now to the drawings and more particularly 5 to FIGS. 1 and 2, there is shown a window-type air conditioner having an outer casing 20 illustrated in dotdash lines together with a sealed motor compressor unit 22, a support bracket 24 for fan motor 25, having a propeller fan 26 mounted on its shaft 27 which draws in outside air through the louvers 28 around the sealed unit 22 and thence through the condenser 30 and out through the discharge louvers 32 at the back of the outer casing 20 to the outside air. All these portions are illustrated in dot and dash lines since they illustrate a known form of window air conditioner.

A transverse upright bulkhead partition or housing 31 extends upwardly from and across the base of'the casing 20 to divide the interior of the unit into a roomside space or compartment 33 projecting into the room enclosure and an outdoors-side space or compartment 34 exposed to the outside air. The irregular bulkhead 31 includes vertical wall sections 35 and 36 and top wall 38 molded with semi-spherical compressor receiving dome 37 and laterally spaced stiffening ribs shown at 39 in FIG. 1. Spaced below top wall 38 is shelf 40 which together with the end walls 42 and 44 form an upper room air discharge chamber 46 having a discharge air opening 48 extending across the front of theunit.

An evaporator 50 is located in front of bellmouth inlet orifice or ring 52 of the centrifugal impeller fan 54 driven by the electric motor 24. The air discharged radially from the fan 54 is directed into a generally vertical flow path by means of a conventional scroll casing partially shown at 55 in FIG. 2 encompassing the fan 54. For details of a typical. scroll casing structure reference should be had to US. Pat. No. 3,305,162 issued Feb. 21, 1967 to W. B. Hall, Jr., the disclosure of which is incorporated by reference herein. The sealed motor compressor unit 22, the condenser 30 and the evaporator 50 are connected together in an operative refrigerant circuit such as may be similar to that shown in the Gould et al. US. Pat. No. 2,945,362 issued July 19, I960. The conventional fan scroll casing 55 is provided with a discharge air outlet opening 56 coinciding with the opening in tbe horizontal shelf 40 having a skewed curled edge cut-off 57 at the throat section of the scroll. The vertical partition wall section 36 is also provided with a rectangular first opening 58 surrounded by a gasket 60 of rubber-like material. The opening 58 communicates with the outer housing compartment 34 through which stale or contaminated air may be removed from the room and exhausted into the compartment 34 from whence it isv subsequently discharged into the outside atmosphere through louvers 32.

A flapper type door or damper 62 for opening 58 is shown adapted to be placed in the rectangularly shaped exhaust air outlet opening. The flapper type door 62 may be made of flexible plastic material having downtumed edges 64 such that when the door is closed extend into sealing engagement with the gasket 60 to seal the opening 58. The door is provided with an integral flexible hinge 66 forming a pivot or hinge section which connects to an angle-shaped anchoring section 68. This angle-shaped anchoring section 68 is held in place by a bent sheet metal bracket 70 which extends over the anchoring section 68 and is fastened by a pair of screws 72 to the partition wall 38. The bracket 70 includes an extension 74 extending upwardly at an angle over the edge of the door containing a plastic eyelet 76. A cord or cable 78 has one end anchored by the anchorage 80 to a central portion of the door 62 and extends through the eyelet 76 and an eyelet 82 in the horizontal wall section 40 and an eyelet 82 in the horizontal wall section 111 and an eyelet 84 in the lanced flange 86 of the air control mounting bracket 88 shown in FIG. 6, to a drum 90 on which it is wound and fastened. The drum 90 is fixed to a shaft 92 which is adapted to be selectively manually turned by an external knob 94. The bracket 88 is suitably afiixed to the side of casing 20 as by screws 96.

Extending toward the free edge of the door is a mousetrap spring 98 having curled portions 100 over the anchoring section 68 and having projecting ends of the spring 98 when the knob 94 is turned to wind the cord or cable 78 upon the drum 90. The shaft 92 is provided with sufficient friction to hold the drum 90 in any adjusted position. The construction of the exhaust door 62 disclosed is only representative of one type .of exhaust door and not a part of the instant invention. For a detailed description of one such door reference should be had to the above-mentioned U.S. Pat. No. 3,305,162 which is assigned to the same assignee as the instant application.

An integrally formed vertically disposed compartment or control box 108 has its rear wall 110 and a top wall 11 1 extending inwardly from casing sidewall 42 having tbe configuration shown to form with vertical wall 112 of the control box 108. Vertical partition and locating wall 116, having an open center section, extends transversely inwardly from both wall 1 12 and side wall 44 to points adjacent theextremities of centrifugal fan 54 and is closed by 'shroud wall-120 supported on 8 (FIG. 1) and is affixed thereto by suitable means such as screws 122. Vertical stiffening ribs 124 and 126 may 'be integrally formed in the shroud wall 120 which wall is preferably molded of high impact polystyrene. The shroud wall 120 together with the locating wall 116 form a composite partition wall. The shroud wall in-, cludes a bellmouth inlet orifice 52 positioned concentric with the impeller blower wheelof fan 54. As best seen in FIG. 5a partition wall combined circular fresh air inlet opening includes opening 128 in partition wall 120 aligned in concentric fashion with a slightly larger circular fresh air opening 130 in the locating wall 116 such that the combined opening is oriented a defined distance to the left and below inlet orifice 52 as seen in FIG. 3. The shroud wall 120 is formed integral with shelf 40 and a vertically extending end flange 132 in juxtaposition to the casing sidewall 44 so as to be suitably secured thereto as by screws 134 as shown in F IG. 1. An arcuate flange 138 extending vertically from an intermediate portion of shelf 40 forms a sidewall of outlet 56 and is secured by screw 140. The shroud wall 120 is additionally secured to the housing 31 by ineither side by overlapping the outer surface thereof tegral tabs 142 extending through aligned slots in side wall 44.

The centrifugal room air fan, which includes the combination of blower 54 and scroll casing 55, is arranged to draw air through the evaporator 50 into the suction inlet orifice 52 of the scroll casing and force it out through the upper discharge chamber 46 through which conditioned air is directed back into the room through the discharge opening 48.

For the purpose of regulating the flow of air through the circular fresh air opening 128, 130 in the shroud wall and in the housing wall 116 damper means in the form of a'rot'atable elongated 'or ovalshaped conduit consisting of a one-piece molded plastic element having an elongated outwardly directed U-section cavity which in the preferred form is semi cylindrical or concavoconvex in cross section having semi-spherical scoop-like end walls or surfaces 152 and 154. In the instant form the conduit damper 150 is formed of a high impact polystyrene material having a thickness of the order of 0.060 inches. The conduit damper 150 is positioned with its semi-spherical end 154 overlying opening 128 in 180 concentric fashion with outwardly directed peripheral flange 156 defining a planarinner surface which when located in flush sealed contact with the shroud wall outer surface 158 forms an elongated cavity to divert air entering through fresh air opening 128, 130 into the conduit damper cavity.

The means for rotatably supporting damper conduit 150 on the outer surface of the partition wall include a fastener element 160 in the form of an integrally molded plastic member having an outer circular ring 162 and an offset inner support structure having a spider configuration including a centrally located rectangular hub portion 164 and four radially outwardly directed spokes 166 equally spaced 90 apart. As seen in FIG. 4 each spoke 166 terminates in arcuate troughs 168forming shoulder plates 170, 171, 172 and 173 arranged in quadrature. The four shoulder plates -173 are located in a common plane offset from the plane of the ring 162 and the shoulder plates respective slots 174, 175, 176 and 177 are equally spaced outwardly from the inner surface of the partition wall.

The conduit damper 150 has integral separable attachment locking means for mounting its semi-spherical end 154 about the inlet opening 128, 130 in the form of three spring fingers 180, 181 and 182 projecting normally from peripheral flange 156 and an elongated spring finger 183 projecting from the base of the conduit damper cavity. The fingers are arranged in quadrature or disposed 90 degrees from one another to be accommodated in their respective aligned slots 175, 174, 173 and 176, with their free head portions or extremities 186 being radially yieldable in response to lateral pressures exerted thereagainst. v

The entering extremities or heads 186 of the fingers -183 are beveled or chamfered to, facilitate initial insertion within their aligned slots 174-177. Each of the spring fingers have a pair of lower beveled paired abutment elements 188 and 189 axially spaced from the undersurface of the head portions'186 by a distance to allow the ring 162 to partially telescope within the inlet opening 128 forrelative rotation therein. It will be noted in FIG. 3 that the paired abutment elements 188,

189 are spaced from flange 156 a distance slightly in excess of the thickness of shroud wall 120 to thereby snugly engage the edge of opening 128 and the exposed surface 190 of the shroud wall to allow pivotal movement therebetween. It will be noted in FIG. 4 that the spring arm 183 has a gusset support 192 slotted at 194 to allow movement of head 186 while its associated slot 176 is keyed at 196 to receive the gusset 192 therein.

As seen in FIG. 4 the opposed corners of the fastening elements hub 164 have integral posts 198 and 199 extending axially therefrom toward the conduit 150, such that when the fastening element 160 is secured in openings 128, 130 in cooperation with rotatable conduit 150 a Z-shaped wire spring 200 is located therebetween having its curled portions 204 and 206 located about aligned posts 198, 199 respectively and retained thereon by push nuts 208 (FIG. 5). The housing wall 116 is provided with integrally molded slotted blocks 210 and 212 whereupon the free ends 201 and 202 of the wire spring 200 are located in the slotted blocks 210 and 212, respectively, exerting forces in opposed relation such that the conduit damper is biased in a clockwise direction indicated by arrow 214 as viewed in FIG. 5. By virtue of the above-described arrangement the conduit damper is biased in a counterclockwise closed position, as viewed in FIG. 2, with peripheral flange 156 in continuous flush contact with the planar surface 158 of shroud wall 120 to prevent fresh air from escaping from the conduit damper 150.

To insure an effective seal between the continuous flange 156 and the shroud wall 120, wedge means 220 in the form of an L-shaped integral bracket 220 is formed on the inward surface 158 of shroud wall 120 as shown in FIG. 8. As seen in FIG. the L-shaped bracket 220 has a tapered slot 222 for the reception of a wedge-shaped protuberance 224 on flange 156 to lock the conduit damper flange 156 in substantial airtight engagement with the shroud wall surface 158.

The rotatable fastening element 160 has a cord or cable 230 anchored to the shoulder plate 170 by anchorage 232 and extends through an eyelet 234 in wall 1 12 and an eyelet 236 in side flange 238 of bracket 88 to drum 90 on which it is wound and fastened in the opposite direction to cord 78 of the exhaust damper 58. Control knob 94, provided with an indicating pointer (not shown), operates such that when turned in a clockwise direction as viewed in FIG. 2 the drum 90 is rotated until cam portion 240 of leaf spring 242 engages a first drum detent (not shown) with the pointer indicating the exhaust damper 58 is one-half open. Further rotation of knob 94 continues winding cord 78 until cam 240 engages a second detent with the pointer indicating that the damper 58 is full open. Control knob 94 may be rotated in a counterclockwise direction returning the pointer to an OFF position closing exhaust damper 58 determined by the cam 24 engaging another detent.

When the knob 94 and drum 90 are turned still further in a counterclockwise direction to a single FRESH AIR position the conduit damper 150 is rotated clockwise away from stop post 239 to its dashed line position 150 disposed in the path of the suction orifice (FIG. 2) resulting in approximately one-fifth or percent of the suction inlet 52 being interrupted so as to prevent passage of a proportionate volume of air through the evaporator when the conduit damper 150 is in its positive open position.

By virtue of having the scoop end 152 of the damper 150 located at the suction entrance 52 a negative pressure is created in the conduit damper causing fresh air to be drawn through the superposed inlets 128 and 130 and into the blower 25 for mixture with recirculated room air and discharged into the room being conditioned. The recirculated room air may be conditioned simply by the mixture therewith of outside fresh air via conduit without a lowering of its temperature or the room air may be first cooled by the evaporator 50 and then mixed with fresh outside air.

It will be noted in FIGS. 3, 4 and 7 that a rectangular screen 250 is provided for preventing the passage of bugs through the conduit 150. The screen is readily positioned in opposed slots 252 integrally formed in conduit damper 150 by integral wing members 256 to allow for ease of cleaning or replacement of screen 250.

While the embodiment of the presentinvention herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted.

We claim:

1. An air flow arrangement including a partition wall having a centrifugal fan scroll inlet orifice therein, a centrifugal impeller positioned in said fan scroll, said partition wall having a fresh air opening spaced a defined distance from said inlet orifice, a molded onepiece conduit member comprising a body portion having an axially elongated outwardly directed hollow cavity including semi-spherical walls at each end, said conduit member having a continuous outstanding peripheral flat flange portion surrounding the elongated conduit mouth, means for rotatably supporting said conduit member on said partition wall about one semi-spherical pivotal end portion which is positioned in concentric fashion over said fresh air opening, whereby said conduit members axis of rotation coincides with the principal axis of said fresh air opening, said rotational support means resiliently biasing said conduit member in a first pivoted position away from said inlet orifice such that said conduit member peripheral flat flange is in continuous flush contact with said partition wall closing the conduit mouth and thereby preventing air flow through the hollow cavity of said conduit member, means for rotating said conduit member to a second open position with at least a portion of its opposite semi-spherical free end extending into the path of said partition wall intake orifice causing the free end portion of the conduit mouth to be placed in communication with said intake orifice, whereby fresh air is drawn in through said fresh air opening and through the elongated cavity of said conduit member for discharge into the fan scroll.

2. The air flow arrangement according to claim' 1, whereby approximately 20 percent of the centrifugal fan scroll inlet orifice area is interrupted by said opposite semi-spherical end of said conduit member extending into the path of said partition wall intake orifice.

3. The air flow arrangement according to claim 1 whereby an L-shaped bracket is positioned on the outer surface of said partition wall for engaging a portion of said peripheral flange adjacent said other semi-spherical free end upon said conduit member being returned to its biased closed position to reatin said peripheral flat flange in flush abutting engagement with said partition wall outer surface.

4. An air flow arrangement including a partition wall having a centrifugal fan scroll inlet orifice therein, a centrifugal-impeller positioned in said fan scroll, said partition wall having a fresh air inlet opening spaced a defined distance from said partition wall inlet orifice, a

molded one-piece conduit member comprising a body portion having a planar inner surface and an elongated outwardly directed concavo-convex section cavity including semi-spherical walls at each end, means for rotatably supporting said conduit member on the outer surface of said partition wall with one semi-spherical end wall positioned in concentric fashion about said fresh air opening, said conduit member planar inner surface forming a continuous outstanding peripheral flange defining an elongated oval-shaped conduit mouth, a plurality of integral spring fingers projecting from said one semi-spherical end wall normal to said conduit inner planar surface and extending through said fresh air opening, said rotational support means including a circular ring partially telescoped within said fresh air opening adapted to be supported on the inner side of said partition wall, said circular ring including slot means therein aligned with each of said spring fingers allowing said fingers to spring into their associated slot means for locking engagement therewith, abutment means on said fingers being sprung into the fresh air opening for rotatably securing said conduit member on said partition wall outer surface, whereby said conduit members axis of rotation coincides with the center of said fresh air. opening, said circular ring having spring means extending outwardly therefrom for retention on the inner surface of said partition wall, said spring means resiliently biasing said conduit member in a first rotational position such that said conduit member peripheral flange is in continuous flush contact with said partition wall outer surface closing said conduit mouth and thereby preventing air flow through said fresh air opening, means for rotating said conduit member to a second ventilating position with a portion of its opposite semi-spherical free end wall extending into the path of said centrifugal fan scroll intake orifice such that a portion of said conduit members mouth is placed in communication with said intake orifice whereby fresh air is drawn through said fresh air opening intothe fan scroll via said conduit member to combine with the air flow entering said intake orifice.

5. In an air conditioning unit for conditioning the air within an enclosure the combination comprising: a casing enclosing a condenser compartment and an evaporator compartment separated by a partition wall, said partition wall having a centrifugal fan scroll air flow orifice therein for receiving a stream of indoor air withdrawn from said enclosure and through said evaporator compartment for subsequent discharging of the conditioned air into the enclosure, a fresh air opening in said partition wall in communication with said condenser compartment, a centrifugal impeller in said fan scroll having its axis substantially normal to said partition wall, said fresh air opening in said partition wall spaced a defined distance from said intake orifice, a molded one-piece conduit member comprising a body portion having a planar inner surface and an elongated outwardly directed concavo-convex section cavity including semi-spherical wall surfaces at each end, said conduit inner surface formed by a continuous outstanding peripheral flange defining an elongated ovalshaped cavity mouth, means for rotatably supporting said conduit member on the evaporator compartment outer surface of said partition wall such that one semispherical end surface is positioned in concentric fashion over said fresh air opening with its axis of rota tion coinciding with the principal axis of said fresh air opening, said rotational support means including a circular ring partially telescoped within said fresh air opening adapted to be supported on the condenser compartment inner side of said partition wall, attachment means on said conduit member extending through said fresh air opening adapted to engage said ring and the edge of said fresh air opening for rotatably securing said conduit member on said partition wall outer surface, whereby said conduit member and said ring rotate in unison about the principal axis of said fresh air opening, means for resiliently biasing said conduit member in a first position such that said conduit peripheral flange is in continuous flush contact with said partition wall outer surface closing said conduit mouth and said fresh air opening, manual control means for rotating said conduit member against said biasing means to a second vented position, whereby said conduit members free semi-spherical end surface partially extends into the area of said partition wall orifice causing a portion of said conduit mouth to be placed in communication with said orifice whereby outside air is drawn in from said condenser compartment through said fresh air opening and said conduit cavity for discharge into said impeller intak-e orifice for mixture with conditioned air for subsequent return to the enclosure.

' 6. In an air conditioning unit for conditioning the air within an enclosure the combination comprising: a cas-. ing enclosing a condenser compartment and an evaporator compartment separated by a partition wall, 1

said partition wall having a centrifugal fan scroll air flow orifice therein for receiving a stream of indoor air withdrawn from said enclosure and through said evaporator compartment for subsequent discharging of the conditioned air into the enclosure, a fresh air opening in said partition wall in communication with said condenser compartment, a centrifugal blower wheel in said fan scroll having its axis substantially normal to said partition wall, said fresh air opening in said partition wall spaced a defined distance from said intake orifice, a molded one-piece conduit damper comprising a' body portion having a planar inner surface and an elongated outwardly directed concavo-convex section cavity including semi-spherical wall surfaces at each end, said conduit inner surface formed by a continuous outstanding elongated oval-shaped peripheral flange defining an elongated oval-shaped cavity mouth, means for rotatably supporting said conduit damper on the evaporator compartment outer surface of said partition wall such that one semi-spherical end surface is positioned in concentric fashion over said fresh air opening with its axis of rotation coinciding with the principal axis of said fresh air opening, said rotational support means including a circular ring partially telescoped within said fresh air opening adapted to be supported on the condenser compartment inner side of said partition wall, said circular ring having outwardly offset integral shoulder plates arranged in quadrature thereon, each said shoulder plate having a slot therein, attachment means on said conduit member extending through said fresh air opening adapted to engage said ring, said attachment means comprising three spring fingers projecting from said one semi-spherical end wall flange and an elongated spring finger projecting from said cavity inner surface, each of said slots aligned with one of said spring fingers allowing said fingers to spring into their associated slots for releasable engagement therewith, abutments on said fingers being sprung onto the edge of said fresh air opening for rotatably securing said conduit damper on said partition wall outer surface, whereby said conduitdamper and said ring rotate in unison about the principal axis of said fresh air opening, means for resiliently biasing said conduit damper in a first position such that said conduit peripheral flange is in continuous flush contact with said partition wall outer surface closing said conduit mouth and said fresh air opening, manual control means for rotating said conduit damper against said biasing means to a second vented position, whereby approximately 20 percent of the centrifugal fan scroll inlet orifice being interrupted by said conduit damper's semi-spherical end surface extending into the area defined by said partition wall orifice causing a portion of said conduit mouth to be placed in communication with said orifice whereby outside air is drawn in from said condenser compartment through said fresh air opening and said conduit cavity for discharge into said impeller intake orifice for mixture with conditioned air for subsequent return to the enclosure;

. 7. The air conditioning unit according to claim 5 whereby said conduit damper being formed with opposed slots integrally formed therein in a plane transverse to the longitudinal axis of said conduit damper intermediate said end wall surfaces, wherein a rectangular-shaped screen may be slidably positioned in said opposed slots to allow for ease of insertion and removal of said screen.

8. The air conditioning unit according to claim 5 whereby said partition wall having an air exhaust opening therein with a hingedly mounted damper door spring-biased to a closed position over said exhaust opening, said manual control means operative upon being turned in a first direction for opening said damper door, and said manual control means operative upon being turned in a second direction causing rotation of said ring and said conduit member to said second vented position. 

1. An air flow arrangement including a partition wall having a centrifugal fan scroll inlet orifice therein, a centrifugal impeller positioned in said fan scroll, said partition wall having a fresh air opening spaced a defined distance from said inlet orifice, a molded one-piece conduit member comprising a body portioN having an axially elongated outwardly directed hollow cavity including semi-spherical walls at each end, said conduit member having a continuous outstanding peripheral flat flange portion surrounding the elongated conduit mouth, means for rotatably supporting said conduit member on said partition wall about one semi-spherical pivotal end portion which is positioned in concentric fashion over said fresh air opening, whereby said conduit member''s axis of rotation coincides with the principal axis of said fresh air opening, said rotational support means resiliently biasing said conduit member in a first pivoted position away from said inlet orifice such that said conduit member peripheral flat flange is in continuous flush contact with said partition wall closing the conduit mouth and thereby preventing air flow through the hollow cavity of said conduit member, means for rotating said conduit member to a second open position with at least a portion of its opposite semi-spherical free end extending into the path of said partition wall intake orifice causing the free end portion of the conduit mouth to be placed in communication with said intake orifice, whereby fresh air is drawn in through said fresh air opening and through the elongated cavity of said conduit member for discharge into the fan scroll.
 2. The air flow arrangement according to claim 1, whereby approximately 20 percent of the centrifugal fan scroll inlet orifice area is interrupted by said opposite semi-spherical end of said conduit member extending into the path of said partition wall intake orifice.
 3. The air flow arrangement according to claim 1 whereby an L-shaped bracket is positioned on the outer surface of said partition wall for engaging a portion of said peripheral flange adjacent said other semi-spherical free end upon said conduit member being returned to its biased closed position to reatin said peripheral flat flange in flush abutting engagement with said partition wall outer surface.
 4. An air flow arrangement including a partition wall having a centrifugal fan scroll inlet orifice therein, a centrifugal impeller positioned in said fan scroll, said partition wall having a fresh air inlet opening spaced a defined distance from said partition wall inlet orifice, a molded one-piece conduit member comprising a body portion having a planar inner surface and an elongated outwardly directed concavo-convex section cavity including semi-spherical walls at each end, means for rotatably supporting said conduit member on the outer surface of said partition wall with one semi-spherical end wall positioned in concentric fashion about said fresh air opening, said conduit member planar inner surface forming a continuous outstanding peripheral flange defining an elongated oval-shaped conduit mouth, a plurality of integral spring fingers projecting from said one semi-spherical end wall normal to said conduit inner planar surface and extending through said fresh air opening, said rotational support means including a circular ring partially telescoped within said fresh air opening adapted to be supported on the inner side of said partition wall, said circular ring including slot means therein aligned with each of said spring fingers allowing said fingers to spring into their associated slot means for locking engagement therewith, abutment means on said fingers being sprung into the fresh air opening for rotatably securing said conduit member on said partition wall outer surface, whereby said conduit member''s axis of rotation coincides with the center of said fresh air opening, said circular ring having spring means extending outwardly therefrom for retention on the inner surface of said partition wall, said spring means resiliently biasing said conduit member in a first rotational position such that said conduit member peripheral flange is in continuous flush contact with said partition wall outer surface closing said conduit mouth and thereby preventing air flow through said fresh air opening, mEans for rotating said conduit member to a second ventilating position with a portion of its opposite semi-spherical free end wall extending into the path of said centrifugal fan scroll intake orifice such that a portion of said conduit members'' mouth is placed in communication with said intake orifice whereby fresh air is drawn through said fresh air opening into the fan scroll via said conduit member to combine with the air flow entering said intake orifice.
 5. In an air conditioning unit for conditioning the air within an enclosure the combination comprising: a casing enclosing a condenser compartment and an evaporator compartment separated by a partition wall, said partition wall having a centrifugal fan scroll air flow orifice therein for receiving a stream of indoor air withdrawn from said enclosure and through said evaporator compartment for subsequent discharging of the conditioned air into the enclosure, a fresh air opening in said partition wall in communication with said condenser compartment, a centrifugal impeller in said fan scroll having its axis substantially normal to said partition wall, said fresh air opening in said partition wall spaced a defined distance from said intake orifice, a molded one-piece conduit member comprising a body portion having a planar inner surface and an elongated outwardly directed concavo-convex section cavity including semi-spherical wall surfaces at each end, said conduit inner surface formed by a continuous outstanding peripheral flange defining an elongated oval-shaped cavity mouth, means for rotatably supporting said conduit member on the evaporator compartment outer surface of said partition wall such that one semi-spherical end surface is positioned in concentric fashion over said fresh air opening with its axis of rotation coinciding with the principal axis of said fresh air opening, said rotational support means including a circular ring partially telescoped within said fresh air opening adapted to be supported on the condenser compartment inner side of said partition wall, attachment means on said conduit member extending through said fresh air opening adapted to engage said ring and the edge of said fresh air opening for rotatably securing said conduit member on said partition wall outer surface, whereby said conduit member and said ring rotate in unison about the principal axis of said fresh air opening, means for resiliently biasing said conduit member in a first position such that said conduit peripheral flange is in continuous flush contact with said partition wall outer surface closing said conduit mouth and said fresh air opening, manual control means for rotating said conduit member against said biasing means to a second vented position, whereby said conduit member''s free semi-spherical end surface partially extends into the area of said partition wall orifice causing a portion of said conduit mouth to be placed in communication with said orifice whereby outside air is drawn in from said condenser compartment through said fresh air opening and said conduit cavity for discharge into said impeller intake orifice for mixture with conditioned air for subsequent return to the enclosure.
 6. In an air conditioning unit for conditioning the air within an enclosure the combination comprising: a casing enclosing a condenser compartment and an evaporator compartment separated by a partition wall, said partition wall having a centrifugal fan scroll air flow orifice therein for receiving a stream of indoor air withdrawn from said enclosure and through said evaporator compartment for subsequent discharging of the conditioned air into the enclosure, a fresh air opening in said partition wall in communication with said condenser compartment, a centrifugal blower wheel in said fan scroll having its axis substantially normal to said partition wall, said fresh air opening in said partition wall spaced a defined distance from said intake orifice, a molded one-piece conduit damper comprising a body portion having a planar inner surface and an elongated outwardly directed concavo-convex section cavity including semi-spherical wall surfaces at each end, said conduit inner surface formed by a continuous outstanding elongated oval-shaped peripheral flange defining an elongated oval-shaped cavity mouth, means for rotatably supporting said conduit damper on the evaporator compartment outer surface of said partition wall such that one semi-spherical end surface is positioned in concentric fashion over said fresh air opening with its axis of rotation coinciding with the principal axis of said fresh air opening, said rotational support means including a circular ring partially telescoped within said fresh air opening adapted to be supported on the condenser compartment inner side of said partition wall, said circular ring having outwardly offset integral shoulder plates arranged in quadrature thereon, each said shoulder plate having a slot therein, attachment means on said conduit member extending through said fresh air opening adapted to engage said ring, said attachment means comprising three spring fingers projecting from said one semi-spherical end wall flange and an elongated spring finger projecting from said cavity inner surface, each of said slots aligned with one of said spring fingers allowing said fingers to spring into their associated slots for releasable engagement therewith, abutments on said fingers being sprung onto the edge of said fresh air opening for rotatably securing said conduit damper on said partition wall outer surface, whereby said conduit damper and said ring rotate in unison about the principal axis of said fresh air opening, means for resiliently biasing said conduit damper in a first position such that said conduit peripheral flange is in continuous flush contact with said partition wall outer surface closing said conduit mouth and said fresh air opening, manual control means for rotating said conduit damper against said biasing means to a second vented position, whereby approximately 20 percent of the centrifugal fan scroll inlet orifice being interrupted by said conduit damper''s semi-spherical end surface extending into the area defined by said partition wall orifice causing a portion of said conduit mouth to be placed in communication with said orifice whereby outside air is drawn in from said condenser compartment through said fresh air opening and said conduit cavity for discharge into said impeller intake orifice for mixture with conditioned air for subsequent return to the enclosure.
 7. The air conditioning unit according to claim 5 whereby said conduit damper being formed with opposed slots integrally formed therein in a plane transverse to the longitudinal axis of said conduit damper intermediate said end wall surfaces, wherein a rectangular-shaped screen may be slidably positioned in said opposed slots to allow for ease of insertion and removal of said screen.
 8. The air conditioning unit according to claim 5 whereby said partition wall having an air exhaust opening therein with a hingedly mounted damper door spring-biased to a closed position over said exhaust opening, said manual control means operative upon being turned in a first direction for opening said damper door, and said manual control means operative upon being turned in a second direction causing rotation of said ring and said conduit member to said second vented position. 